Effet chez le porcelet d'une exposition à un régime co-contaminé en ...

INTRODUCTIONSubstances investigated as potential organic mycotoxin-binding agents include among othersactivated charcoal, alfalfa, canola oil bleaching clays, organic polymers such as cholestyramin,polyvinylpolypyrrolidone (PVPP), yeast cell walls and components thereof as well as bacterial cells.a) Activated charcoalActivated charcoal is known as one of the most effective and non-toxic, but also mostunspecifically acting group of sorbents with a high surface to mass ratio (500-3500 m 2 /g). They areformed by pyrolysis of several organic compounds. They can efficiently adsorb most of themycotoxins in aqueous solution, whereas different activated charcoals have less or even no effectsagainst mycotoxicosis (Kolossova et al., 2009).Activated charcoal has been investigated for its ability to adsorb mycotoxins both, in vitro and invivo, being verified to adsorb zearalenone, deoxynivalenol and nivalenol in vitro, using agastrointestinal model, and aflatoxins, ochratoxin A and fumonisins rather efficiently in vivo (CAST,2003, Pettersson, 2004; Kolossova et al., 2009).In vitro aflatoxin adsorption tests with different activated charcoals showed good results atdifferent pH values (Huwig et al., 2001). In vivo, certain granulated activated carbons (GACs)decreased conversion of aflatoxin B1 to aflatoxin M1 in Friesian cows by 40.6 to 73.6% whenincluded in the diet at concentrations of 2.0% (CAST, 2003). Improvements in body weight gains andfeed intake of chickens were verified when activated charcoal was added to AF-contaminated diets(Edrington et al., 1997; Dalvi and Ademoyero 1983; Dalvi and McGowan 1984 and Jindal et al., 1993).However conflicting results have been verified, possibly due different types of activated charcoalsused.Successful in vitro OTA adsorption tests with activated charcoal showed that 1% product additionleads to complete adsorption of ochratoxin A from aqueous solutions not being influenced by pHvaluesranging from 3-8 (Plank et al., 1990).In addition, some trials have been performed with superactivated charcoal which differs fromactivated charcoal by its reduced particle size, higher surface area and a chemical modification duringthe manufacturing process. Superactivated charcoal was evaluated for its effectiveness in preventingdeath in rats given an oral lethal dose of 8 mg/kg body weight of T-2 toxin. The median effectivedose of oral superactive charcoal in preventing deaths in rats was found to be 0.175 g/kg bodyweight. At the end of the trial it was concluded that one gram per kilogram body weight oralsuperactive charcoal enhanced survival times and survival rates in rats given T-2 toxin (Galey et al.,1987). In vivo, orally administered activated charcoal was assessed for treatment of acute oral orparenteral exposure to T-2 toxin in mice. Charcoal treatment (7 g/kg) either immediately or 1 hr after78